Abstract: A structure (1) for providing a physical or visual barrier comprises at least one post (2) mounted to a supporting surface and to which is secured at least one slat (8) by at least one wedge (10). The post (2) has a beam 31 (16) extending upwards from a footing. The beam (16) comprises at least one longitudinally extending plate which at least partially encloses a hollow (18). The beam has at least one plate that extends between opposite left and right sides (33, 34). The beam has at least one plate that extends between opposite front and rear sides (31, 32). The beam (16) is cut through by at least one slot (28) extending rearwards from the front side (31) part of the way towards the rear side (32). The slot (28) is configured to receive a portion of a slat (8) when inserted into the slot (28) in an insertion direction from the front side (31) of the beam (16). The slat (8) then extends laterally away from at least one of the sides (33, 34).

Abstract: The lasing output of a laser diode (1) is controlled by the current through the diode (1). The laser diode (1) is driven by a switched mode drive circuit in which a pulsed signal is applied to a smoothing circuit, typically including a capacitor C and an inductor L, arranged to provide a smoothed output voltage whose magnitude depends on the pulse width of the drive signal.

Abstract: An optical system for producing a high power light source comprises a number of laser diodes, or similar sources, which emit light from an emission stripe 8 having a long dimension a (x-axis) and a short dimension b (y-axis) and which have a higher numerical aperture in the y-axis than in the x-axis. The laser beams 9 are collimated by a lens 10 and focused onto an optical fiber by a further lens 20. Prior to the focusing, the collimating beams 11 are anamorphically expanded/reduced by beam shaping means 12 so that the width of each beam 11 in the x-axis is increased in relation to the width in the y-axis. The images 21 produced on the fiber end are thus anamorphically magnified so that thte anamorphic ratio between the magnification of the stripe 8 in the y-axis and in the x-axis is greater than one.

Abstract: An optical system for producing a high power light source comprises a number of laser diodes, or similar sources, which emit light from an emission stripe 8 having a long dimension a (x-axis) and a short dimension b (y-axis) and which have a higher numerical aperture in the y-axis than in the x-axis. The laser beams 9 are collimated by a lens 10 and focused onto an optical fibre by a further lens 20. Prior to the focusing, the collimating beams 11 are anamorphically expanded/reduced by beam shaping means 12, so that the width of each beam 11 in the x-axis is increased in relation to the width in the y-axis. The images 21 produced on the fibre end are thus anamorphically magnified so that the anamorphic ratio between the magnification of the stripe 8 in the y-axis and in the x-axis is greater than one.

Abstract: A laser diode light source comprises at least two laser diodes (1,2). The beams (3,4) of the diodes (1,2) are combined together by, for example, a polarising beam combiner (11) and the combined beam (18) is focused by a lens (19) onto an optical cable (20). The beams (3,4) are also acted on in the long direction of the laser stripes of the diodes (1,2) by anamorphic beam shaping means (7,8;9,10) to reduce the length of the image formed at the end of fibre (20) by a predetermined factor, chosen such that the numerical aperture of the focused beam (18) in said long direction does not substantially exceed that of the optical fibre (20).

Abstract: The invention provides a photocoagulator using an infrared laser diode source (70). A dichroic beam splitter (68) is used to combine the optical path of the laser system with the viewing system. Such an arrangement affords the clinician an uninterupted, uncolor view of the patient's eye during treatment, without any risk of damage to the clinician's eye. There is also provided an alignment system using a visible laser diode (80). The alignment system may include a number of mutually non parallel beams which pass through different portions of the pupil and provide information on aim, focus and vignetting.